Complete all story locations as Bio-Specialist

Get the killing blow on an enemy with at least two Devastators' beams hitting each other.

Defeat Del Lago.

Reroll weapon or equipment attributes 100 times

Have all different primary weapons in your inventory, with at least Rare rarity

Parry an enemy with a knife.

Drink 6 health potions within a level without dying or restarting

Completed Chapter 3 of Episode 1

Kill 250 zombies with modified weapons.

Sever 100 limbs.

Reach level 25.

Save 5 people besieged by zombies.

Set 5 enemies on fire and then kill them with explosives.